Frost Dates & Planting Calendar for Security-Widefield, CO

Plan your garden around Security-Widefield, CO's typical frost-free growing season, using NOAA climate normals and a 42-crop planting calendar built for this location.

Last Spring Frost
May 3
Safe May 15 Typical May 3 Risky Apr 22
First Fall Frost
October 8
Safe Sep 26 Typical Oct 8 Risky Oct 19
Growing Season
158 days
Typical last frost to typical first frost.
USDA Hardiness Zone
Zone 6a
A classic four-season climate with cold winters and a solid summer growing season.
Data: NOAA station COLORADO SPRINGS MUNI AP, CO US, 7.3 km away.
days until the typical last spring frost

Monthly Temperatures

Monthly normal temperatures (°F) 10°30°50°70°90° JFMAMJJASOND
Avg. high Avg. temp Avg. low

Planting Calendar

Vegetables
CropStart indoorsDirect sowTransplantFall plantingMaturityNotes
Tomato Mar 8 – Mar 22 May 10 – May 17 60–85 days Start indoors 6-8 weeks before last frost; transplant out 1-2 weeks after last frost once soil has warmed.
Pepper Feb 22 – Mar 8 May 10 – May 24 60–90 days Slow to germinate; start indoors 8-10 weeks before last frost. Transplant only once nights stay above 55F, 1-3 weeks after last frost.
Eggplant Feb 22 – Mar 8 May 17 – May 24 65–85 days Warm-season crop, similar timing to pepper; needs consistently warm soil (65F+) to transplant.
Cucumber Apr 5 – Apr 12 May 10 – May 17 May 10 – May 17 50–65 days Can be started indoors 3-4 weeks before transplanting, or direct-sown 1-2 weeks after last frost once soil is warm.
Zucchini Apr 12 – Apr 19 May 10 – May 24 May 10 – May 17 45–55 days Fast-growing squash; direct sow 1-3 weeks after last frost, or start indoors 2-3 weeks early for a head start.
Winter Squash Apr 5 – Apr 12 May 10 – May 24 May 10 – May 17 80–110 days Long season; direct sow after soil warms, or start indoors 3-4 weeks before last frost in short-season climates.
Pumpkin May 10 – May 24 90–120 days Direct sow 1-3 weeks after last frost; back-time from your first fall frost so the 90-120 day maturity window lands before it.
Watermelon Apr 5 – Apr 12 May 17 – May 24 70–90 days Needs warm soil (65F+); start indoors 3-4 weeks before last frost, transplant 2-3 weeks after last frost.
Cantaloupe Apr 5 – Apr 12 May 17 – May 24 70–90 days Same warm-soil requirements as watermelon; avoid disturbing roots when transplanting.
Corn May 3 – May 17 60–100 days Direct sow at last frost to 2 weeks after, once soil reaches 60F; does not transplant well. Succession sow every 2 weeks.
Green Bean May 3 – May 17 50–65 days Direct sow at last frost to 2 weeks after, once soil has warmed; frost-tender, do not rush.
Pea Mar 22 – Apr 5 55–70 days Cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked.
Lettuce Apr 5 – Apr 19 Aug 13 – Aug 27 45–60 days Cold-hardy; direct sow 2-4 weeks before last frost. Also transplantable from indoor starts.
Spinach Mar 22 – Apr 5 Aug 13 – Aug 27 40–50 days Very cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked.
Kale Apr 5 – Apr 19 Jul 30 – Aug 13 50–65 days Cold-hardy; direct sow 2-4 weeks before last frost or start indoors for earlier transplants.
Arugula Apr 5 – Apr 19 Aug 27 – Sep 3 30–40 days Fast-growing, cold-tolerant green; direct sow 2-4 weeks before last frost, succession sow every 2-3 weeks.
Swiss Chard Apr 12 – Apr 26 50–60 days Fairly cold-hardy; direct sow 1-3 weeks before last frost. Tolerates light frost in fall too.
Broccoli Mar 15 – Mar 29 Apr 12 – Apr 19 Aug 6 – Aug 13 55–80 days Start indoors 5-7 weeks before last frost; transplant out 2-3 weeks before last frost (hardens off to light frost).
Cauliflower Mar 15 – Mar 29 Apr 19 – Apr 26 Jul 30 – Aug 6 55–85 days Fussier than broccoli about temperature swings; start indoors 5-7 weeks before last frost, transplant 1-2 weeks before last frost.
Cabbage Mar 15 – Mar 29 Apr 5 – Apr 19 Jul 30 – Aug 13 60–100 days Cold-hardy; start indoors 5-7 weeks before last frost, transplant 2-4 weeks before last frost.
Brussels Sprouts Mar 15 – Mar 29 Apr 12 – Apr 26 90–110 days Long-season crop best timed to mature after a light fall frost for sweetest flavor; start indoors 5-7 weeks before last frost.
Carrot Apr 5 – Apr 19 Jul 16 – Jul 30 60–80 days Direct sow only (does not transplant); sow 2-4 weeks before last frost, as soon as soil can be worked.
Beet Apr 5 – Apr 19 Jul 30 – Aug 13 50–65 days Direct sow 2-4 weeks before last frost; tolerates light frost.
Radish Mar 29 – Apr 12 Aug 27 – Sep 10 22–30 days Very fast and cold-hardy; direct sow 3-5 weeks before last frost, as soon as soil can be worked.
Turnip Apr 5 – Apr 19 Jul 30 – Aug 13 40–60 days Cold-hardy; direct sow 2-4 weeks before last frost.
Onion Feb 22 – Mar 8 Apr 5 – Apr 19 90–120 days Start seeds indoors 8-10 weeks before last frost (or use sets/transplants); set out 2-4 weeks before last frost, very cold-tolerant as seedlings.
Garlic Sep 10 – Sep 24 240–270 days Fall-planted crop only; not planted in spring in most climates.
Potato Apr 5 – Apr 19 70–120 days Plant seed potatoes 2-4 weeks before last frost, as soon as soil can be worked and is above 45F; light frost on emerging foliage is usually tolerated.
Sweet Potato May 17 – May 31 90–120 days Set out slips 2-4 weeks after last frost once soil is thoroughly warm (65F+); very frost/cold sensitive.
Asparagus Apr 5 – Apr 19 730–1095 days Perennial; plant crowns 2-4 weeks before last frost as soon as soil can be worked. Takes 2-3 years to full production.
Herbs
CropStart indoorsDirect sowTransplantFall plantingMaturityNotes
Basil Mar 22 – Mar 29 May 10 – May 17 50–70 days Very frost/cold sensitive; start indoors 5-6 weeks before last frost, transplant only after all danger of frost (1-2 weeks after) and nights stay warm.
Cilantro Apr 12 – Apr 26 Aug 13 – Aug 27 45–70 days Cool-season, bolts in heat; direct sow 1-3 weeks before last frost, succession sow through spring.
Parsley Mar 8 – Mar 22 Apr 19 – Apr 26 70–90 days Slow to germinate; start indoors 6-8 weeks before last frost, transplant 1-2 weeks before last frost (biennial, cold-tolerant).
Dill Apr 12 – Apr 26 40–60 days Taprooted, does not transplant well; direct sow 1-3 weeks before last frost, succession sow through summer.
Oregano Mar 8 – Mar 22 May 3 – May 10 80–90 days Perennial herb; start indoors 6-8 weeks before last frost, transplant around/just after last frost date.
Thyme Mar 8 – Mar 22 May 3 – May 10 85–95 days Perennial herb, slow from seed; start indoors 6-8 weeks before last frost, transplant around/after last frost.
Flowers
CropStart indoorsDirect sowTransplantFall plantingMaturityNotes
Sunflower May 10 – May 24 70–100 days Direct sow 1-3 weeks after last frost once soil has warmed; taprooted, resents transplanting.
Zinnia Apr 5 – Apr 12 May 10 – May 24 May 10 – May 17 60–70 days Frost-tender; direct sow 1-3 weeks after last frost, or start indoors 3-4 weeks early for earlier blooms.
Marigold Mar 22 – Apr 5 May 10 – May 17 45–60 days Frost-tender; start indoors 4-6 weeks before last frost, transplant after all frost danger has passed.
Cosmos Apr 5 – Apr 12 May 10 – May 24 May 10 – May 17 60–90 days Easy from direct seed 1-3 weeks after last frost; can also start indoors 3-4 weeks early.
Nasturtium May 10 – May 24 50–65 days Frost-tender, resents root disturbance; direct sow 1-3 weeks after last frost once soil has warmed.
Dahlia May 10 – May 24 90–120 days Plant tubers 1-3 weeks after last frost once soil is warm (60F+); very frost-sensitive.

Date ranges are estimates based on university extension guidelines and this city's NOAA frost normals — not a guarantee. Scroll to see all columns on narrow screens.

Frequently Asked Questions

When is the last frost in Security-Widefield, CO?

Based on 1991–2020 NOAA climate normals for the COLORADO SPRINGS MUNI AP, CO US station, the last spring frost in Security-Widefield typically falls around May 3. A cautious gardener might wait until May 15 (only a 10% chance of a later frost), while April 22 marks an earlier, higher-risk planting date.

When is the first frost in Security-Widefield, CO in fall?

The first fall frost in Security-Widefield typically arrives around October 8. To stay safe, assume frost could start as early as September 26; in milder years it can hold off until October 19.

How long is the growing season in Security-Widefield, CO?

Security-Widefield's average frost-free growing season is about 158 days, running from the typical last spring frost (May 3) to the typical first fall frost (October 8).

What USDA hardiness zone is Security-Widefield, CO in?

Security-Widefield, CO is in USDA plant hardiness zone 6a, per the USDA's 2023 Plant Hardiness Zone Map. A classic four-season climate with cold winters and a solid summer growing season.

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